Adjusting screw lock for adjustable end wrench



Um. 4, 1955 T. F. JACKSON 2,719,45Q

ADJUSTING SCREW LOCK FOR ADJUSTABLE END WRENCH Filed Aug. 4, 1955 I Mr F Jackson 2,719,450 ADJUSTING SCREW noon-FOR ADJUSTABLE WRENCH Theodore F. Jackson, assignor of onesixth-to RoyM. Buck, Belvidere, one-sixth to Donald E. Carlyle, Rockford, and'one-six'th to Carl F. Christensen, Rockford,lll.

Application August4, 1953, Sei'ial No. 372,333

4 Claims. (CL 81-165 This invention relates to afnew and improved adjusting screw lock for an 'adju'sta'ble end wrench.

It is well known that adjustable "end wrenches, commonly called crescent wre'iitih'es, have long been subject to the objection that the movable jaw will not hold its adjustmerih and the're i's"co'riseque'ntly the need for re peatedly correcting the adjustment, T'which is both timeconsuming and very annoying. 1 Various constructions have been devised in an effort to solve this problem, but, so far as I am aware, none has been adopted commercially, and it is my belief that this is because they have been too complicated and expensive in constru ct ion in relation to the advantages offered and because they were not practical from the standpoints of dependability and positive action, and. were not handy and speedy in operation in the unlocking and locking of the adjusting screw or worm when an adjustment has to be made. It is, therefore, the principal object of my invention to provide an adjustable end wrench which is designed to avoid so far as possible all of the objections mentioned and yet meet the various practical requirements enumerated.

The invention is illustrated in the accompanying drawing, in which Fig. l is a side view of an adjustable end wrench having an adjusting screw lock made in accordance with my invention;

Figs. 2 and 3 are longitudinal sections on the broken line 3-3 of Fig. 1, showing the screw locked in Fig. 2 and unlocked in Fig. 3;

Fig. 4 is a section similar to Fig. 2 showing a screw lock of modified or alternative construction;

Fig. 5 is a fragmentary side view of Fig. 4, and

Fig. 6 is an end view of the serrated or saw-toothed end of the locking spring of Figs. 4 and 5.

Similar reference numerals are applied to corresponding parts throughout these views.

Referring to Figs. 1 to 3, the reference numeral 7 designates the handle of an adjustable end wrench, on the enlarged outer end portion of which is defined a head provided with the usual fixed jaw 8 and associated movable jaw 9. The latter is slidably guided, as shown at 10, for adjustment transversely of the head and has rack teeth 11 along the inner edge meshing with the threads 12 of an adjusting screw 13 rotatably mounted on a pin 14 for manual operation in the usual way in a rectangular opening 15 provided in the head. The periphery of the threads 12 is usually knurled or roughened in some other way to provide a good finger grip surface to facilitate manual operation. In accordance with my invention, the screw 13, which may be knurled on the periphery of its threads for a finger grip surface, has parallel grooves 16 cut in the threads in circumferentially spaced relation for locking engagement therein of a tooth 17 on the end of an elongated leaf spring 18 provided by the inwardly bent outer end portion of said spring. The spring 18 is disposed lengthwise of the handle and fastened at its inner end to the handle 7 by screws 19 and is normally bowed outwardly as appears in Fig. 2 and urges its 2,719,450 Patented Oct. 4, 1955 2 toothed end 17 inwardly againstthescrew so asto engage in whichever groove '16 happens to be in register with the tooth, as shown in Fig. 2. Spring 18 is-adapted to be flexed outwardly to the retracted positionshown in Fig. 3 by means of an elongated pin 20 that-isdisposed crosswise of the leaf spring 18 and, inter'meiiiate its ends, is slottedlengthwise, as at 21, and*mount.ed by means of this slot on the leaf spring 18 for sliding'movement lengthwise of said spring. The pin 20 'is movable'back and forth by thumb pressure 'froin anoperativeposition, en-

gaging a punched out stop lug 22, as shown in Figs. 1 and 3, to an inoperative position engaging anot her punched out stop lug 23, as shown in Fig. 2. I11 sliding back and forth on the leaf spring 18, the pin 20 slides on the flat face 24 on the side of the wrench handle, and, in its operative position, as shown in Fig. 3, supports the leaf spring 18 in aposition flexed farther outwardly with its toothed end clear of the screw 13 so that the screw may be adjusted in either direction.

In operation, the jaw 9 is adjusted by means of screw 13 while the spring "18 is held retracted by pin 20 slid to the rear as appears in Figsgl and 3.. After the desired adjustment has been' made the pin 20 is slid forward again, as in Fig. 2, to permit thetooth 17 on spring 18 to move inwardlyunder inherent spring tension and engage in whichever groove '16 registers with the tooth.- 'lfthe tooth happens to abut the screw between the grooves it will, under its inherent tension, snap into onethe inst'ant the screw turns a bitone way or 'the other in response to thrust transmitted to the screw from the jaw 9, after which no further evenslight-changein the Wrench "acljustmentcan occur accidentally,'-or even-by manual operation of screw 13, until the screw is unlocked again.

Referring to Figs. 4-6, the adjusting screw 13 is like screw 13, minus the grooves 16, it being only knurled on the periphery of its threads 12, as indicated at 25, for the double purpose of facilitating manual adjustment and also cooperating with the teeth 17' on locking spring 18 to lock the screw in adjusted position. The teeth 17' are pointed like saw teeth to insure good gripping, and alternate teeth are bent outwardly and intermediate teeth are bent inwardly into the angular relationship shown in Fig. 4, so that one set prevents rotation of the screw in one direction and the other set prevents rotation of the screw in the other direction. The teeth 17 are spaced differently than the threads 12' of screw 13, as indicated, to insure engagement of at least one tooth of each set with the screw in any position of rotary adjustment. Otherwise, this screw-lock construction is the same as that of Figs. 13 and operates the same. This construction is better adapted than the other one to be applied to existing wrenches, because it does not require anything more than the knurling of the screw threads.

It is believed the foregoing description conveys a good understanding of the objects and advantages of my inven tion. The appended claims have been drawn to cover all legitimate modifications and adaptations.

I claim:

1. An adjustable end wrench comprising an elongated handle having an enlarged end portion terminating in a fixed jaw and having an opening provided therein, an adjustable jaw provided with a rack portion slidably mounted on said end portion, a screw rotatably mounted in said opening and meshing with said rack, an elongated flat leaf spring disposed lengthwise of one side of said handle and fixed at one end to the handle and having the other end portion free and flexed outwardly but urged inwardly under inherent spring tension toward the handle and screw and having an inwardly bent edge portion on the extremity of said free end portion defining a tooth portion parallel to the axis of said screw movable sub stantially radially with respect to the screw for engagement and disengagement and normally resiliently engaging the threads on said screw to prevent rotation thereof, and a manually slidable member carried on the outwardly flexed free end portion of said leaf spring and arranged to have slidable engagement also with the handle and movable outwardly toward said inwardly bent edge portion to a position in which said slidable member does not interfere with the inherent locking action of said spring and inwardly to another position in which it holds the free end portion of said spring flexed farther outwardly so that the inwardly bent edge portion is disposed out of locking engagement with said screw.

2. A wrench as set forth in claim 1 including stops on said leaf spring spaced longitudinally thereof which limit the sliding movement of said manually slidable member inwardly and outwardly on said leaf spring.

3. An adjustable end wrench comprising an elongated handle having an enlarged end portion terminating in a fixed jaw and having an opening provided therein, an adjustable jaw provided with a rack portion slidably mounted on said end portion, a screw rotatably mounted in said opening and meshing with said rack, an elongatedflat leaf spring disposed lengthwise of one side of said handle and fixed at one end to the handle and having the other end portion free and flexed outwardly but urged inwardly under inherent spring tension toward the handle and screw and having an inwardly bent edge portion on the extremity of said free end portion defining a tooth portion parallel to the axis of said screw movable substantially radially with respect to the screw for engagement and disengagement and normally resiliently engaging the threads on said screw to prevent rotation thereof, the periphery of the threads being roughened to facilitate manual operation of the screw, the tooth portion of said leaf spring having teeth, some of which are bent outwardly and others of which are bent inwardly with respect to the extremity of said free end portion toward the screw but at approximately the same angle with respect to a radial plane through the axis of rotation of said screw, said teeth being adapted to engage in the roughened periphery more or less positively to prevent rotation in either direction, and a manually slidable member carried on the outwardly flexed free end portion of said leaf spring and arranged to have slidable engagement also with the handle and movable outwardly toward said inwardly bent edge portion to a position in which said slidable member does not interfere with the inherent locking action of said spring and inwardly to another position in which it holds the free end portion of said spring flexed farther outwardly so that the inwardly bent edge portion is disposed out of locking engagement with said screw.

4. A wrench as set forth in claim 3 including stops on said leaf spring spaced longitudinally thereof on the spring which limit the sliding movement of said manually slidable member inwardly and outwardly on said leaf spring.

References Cited in the file of this patent UNITED STATES PATENTS 1,367,408 McClurkin Feb. 1, 1921 1,512,846 Gumprecht Oct. 21, 1924 1,599,162 Brown Sept. 7, 1926 1,749,002 Schneider et al Mar. 4, 1930 2,316,455 Richardson Apr. 13, 1943 FOREIGN PATENTS 31,257 Norway Oct. 11, 1920 454,143 Great Britain Sept. 24, 1936 

